A dialysis device is a device used for removing wastes from blood through a dialyzer, and a filter for purifying dialysis fluid (removal of endotoxin) is normally provided in a dialysis fluid circuit on an upstream side of the dialyzer. Moreover, in online treatment using the dialysis fluid into a blood circuit instead of a physiological saline, a second-stage filter is further provided on a downstream side of said filter in order to reliably realize sufficient purification (Patent Document 1).
Said filter includes, as conventionally known, a cylindrical housing arranged with a longitudinal direction vertically and accommodating a filter material therein, an introduction port provided on a lower part of the housing and introducing the dialysis fluid to an inside, a filtered fluid lead-out port for leading out filtered dialysis fluid having passed through the filter material in the dialysis fluid having been introduced through the introduction port from an upper part of the housing, and an unfiltered fluid lead-out port for leading out unfiltered fluid not having passed through the filter material in the dialysis fluid having been introduced through the introduction port from the upper part of the housing.
The dialysis fluid circuit includes an upstream-side flow path connected to the introduction port of the filter and causing the dialysis fluid to flow into the housing, a downstream-side flow path connected to the filtered fluid lead-out port of the filter and causing the filtered dialysis fluid to flow out from an inside of the housing, and a waste fluid flow path connected to the unfiltered fluid lead-out port and causing the unfiltered fluid to be discharged from the inside of the housing.